1. Field of the Invention
The present invention relates to a power unit supporting apparatus configured to mount a power unit having a configuration in which a speed reduction gear is connected to an end of a power source such as an engine, on a vehicle body.
2. Description of Related Art
Common vehicle power units include longitudinally-mounted power units and transversely-mounted power units. The longitudinally-mounted power unit has a configuration in which a power source and a speed reduction gear are arranged in a front-rear direction of a vehicle body and are connected to each other.
On the other hand, the transversely-mounted power unit has a configuration in which a power source and a speed reduction gear are arranged in a vehicle width direction. The transversely-mounted power unit is constituted by, for example, extending an engine crankshaft in the vehicle width direction and also connecting an input shaft of a transmission serving as a speed reduction gear to an end of the extended crankshaft. The transversely-mounted power unit is accommodated in a power unit accommodating chamber (or engine room) of the vehicle. Thus, the length in the front-rear direction of the power unit accommodating chamber can be reduced.
Various kinds of power unit supporting apparatuses for mounting such a transversely-mounted power unit on a vehicle body are known (see, for example, Japanese Patent Unexamined Publication No. JP-A-2004-148843).
A conventional vehicle power unit supporting apparatus of JP-A-2004-148843 is described below with reference to FIGS. 9A and 9B. FIGS. 9A and 9B are explanatory views illustrating the conventional vehicle power unit supporting apparatus. FIG. 9A illustrates a planar configuration of each of the vehicle power unit and the power unit supporting apparatus. FIG. 9B illustrates a rear configuration of each of the vehicle power unit and the power unit supporting apparatus.
The conventional vehicle power unit supporting apparatus 200 is constructed as follows. That is, a transversely-mounted power unit 203 having a configuration, in which an engine 201 and a transmission 202 are arranged in a vehicle width direction and are connected to each other, is mounted on a vehicle body 205 through a subframe 204.
More specifically, a front mount 212, a rear mount 213, and a transmission lower mount (not shown) are attached to the subframe 204 at a position lower than the position of the center 211 of gravity of the engine 201. Consequently, these mounts can receive the static load of the power unit 203.
Also, the power unit 203 can be supported by left-side and right-side mounts (i.e., a side engine mount 214 and a transmission upper mount 215), which are attached to the vehicle body 205 at positions higher than the position of the center 211 of gravity of the engine 201.
Meanwhile, to enhance the driving stability and the riding comfort of the vehicle 200, it is requested not only to suppress vibrations of the power unit 203 from being transmitted to the vehicle body 205 but to prevent the behavior of the power unit 203 from affecting the vehicle body 205.
For example, when the vehicle 200 is turned to the left or right, a centrifugal force is applied to the vehicle 200 during the turn thereof. At that time, the centrifugal force is also applied to the power unit 203. To sufficiently enhance the driving stability and the riding comfort of the vehicle 200, it is preferable to suppress the influence of the behavior of the power unit 203 serving as a heavy load on the vehicle body 205.